The invention relates to a downhole device for controlling fluid flow through a hydrocarbon fluid production well.
Numerous devices exist for controlling fluid flow in wells. These devices generally comprise a valve body which opens or closes a fluid passage in response to actuation of the valve body by an electric or hydraulic motor.
Since the fluid pressure and pressure differentials across the downhole valve are generally high, powerful electric or hydraulic motors are required which requires a significant space in the generally narrow wellbore and deployment of high power and high voltage or high pressure electric or hydraulic power supply conduits.
It is an object of the present invention to provide a downhole fluid control device for use in a hydrocarbon production well which is compact and can be operated without requiring high voltage or high pressure power supply conduits.
The downhole device according to the invention comprises a deformable chamber which contains a stimuli responsive gel, which gel has a volume that varies in response to variation of a selected physical stimulating parameter, and a fluid passage which is closed off in response to a volume increase of at least part of the gel and the deformable chamber.
Preferably the gel is an electromagnetic field responsive gel which releases water if an electromagnetic field of a certain field strength is exerted to the gel and which absorbs water in the absence of an electromagnetic field and the device is equipped with an electromagnetic field transmitter which is adapted to exert an electromagnetic field of a selected field strength to the gel.